@naveen, I'm guessing the problem is indicated by the comments in the code but, perhaps I assume too much.
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JodrellMay 24 '11 at 8:41

@jodrell: i dont get it. did you? this is what confuse me. ddl.DataSource=ds//error:Object reference not set to an instance of an object. you should see that row count is greater than 0.
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naveenMay 24 '11 at 8:45